1. The Field of the Invention
The present invention relates to electrical contacts and in particular to a double beam contact for use in cam actuated zero insertion force connectors.
2. The Prior Art
Zero or low insertion force electrical connectors are well known, as represented by U.S. Pat. Nos. 3,899,234 and 4,047,782. Each of the known rotary cam actuated low insertion force connectors is somewhat similar in that it comprises a housing having an elongated board receiving opening with a channel at the base of the opening. A rotary cam is positioned in the channel and acts on a cam follower which directly engages contacts located in parallel spaced alignment along both sides of the elongated opening. Rotation of the cam moves the cam follower to drive the contacts normally with respect to the elongated opening so that, in an actuated condition, they will be free of the opening allowing no force insertion of the circuit board and, upon further movement of the cam, the contacts are allowed to drop by their own spring action against the opposite surfaces of the circuit board to make engagement therewith.
While such connectors as described above functioned quite well, the contacts are not able to penetrate any contaminant films that might build up on the contact interface and in particular on the pads of the circuit boards. It is highly desirable that the contacts have a wiping action to displace or break through these films to provide a better contact. However, a feature of the zero insertion force connectors is that there is no wiping action of the contacts against the pads during insertion of a circuit board or engagement therewith.